The value of the equilibrium constant for the reaction below is 40.0 at a specified temperature. What would be the value of that constant for the reverse reaction under the same conditions?

H2(g) + I2(g)  HI(g)

I answered this for you below.

To determine the value of the equilibrium constant for the reverse reaction, we can use the relationship between the equilibrium constants of the forward and reverse reactions.

The equilibrium constant (K) is determined by the concentrations or partial pressures of the reactants and products at equilibrium. For the given reaction:

H2(g) + I2(g) ⇌ HI(g)

The equilibrium constant (K) is given as:

K = [HI(g)] / ([H2(g)] * [I2(g)])

To find the equilibrium constant for the reverse reaction, we can use the relationship that relates the equilibrium constants of the forward and reverse reactions:

K(reverse) = 1 / K(forward)

Therefore, to find the value of the equilibrium constant for the reverse reaction, we can calculate:

K(reverse) = 1 / K(forward) = 1 / 40.0 = 0.025

Hence, the value of the equilibrium constant for the reverse reaction under the same conditions would be 0.025.